NCGS-M001 — Census count of tree state at a declared horizon
- Code: NCGS-M001
- Version: NCGS-2026-11-04
- Approval status: Approved
A full census of the tree individuals planted at a site, or handed over there in the delivered-with-monitoring stratum (ADR-0031), made on one monitoring visit at a declared observation horizon: every tree reached is observed alive or dead with its condition class, care and evidence; trees not reached are unobserved. From the approved observations the methodology computes trees alive, survival rate, trees by condition class and, from T3, establishment rate. Condition assessment is part of this methodology, not a separate one.
underlying principles and assumptions
The tree individual is the unit of observation (ADR-0002); one visit serves several indicators (ADR-0015); a horizon is a checkable window from the planting date, not a label (ADR-0010); an unobserved tree is not a dead tree; the denominator is fixed on planting day and rates roll up by summing, never by averaging; nothing is claimed at a horizon the monitoring period does not reach (ADR-0012); every rate is calculated over scheduled observations only, and an observation outside the plan is kept, counted as unscheduled and never enters a rate (ADR-0020).
methods and procedures
Plan the visit at a horizon reachable in the monitoring plan; at the site, for every tree individual in the planting records, find the tree at its position or by its tag, record alive or dead, the condition class, mulch cover, hole state, soil moisture, stem paint, watering frequency, volume and source, fertilising, pruning, pests observed, cause of death if dead, canopy axes and DBH where measurable, and photograph it; record the visit’s observer, role, time, device location and channel; export computes each observation’s offset from planting; submit the visit for verification review.
data requirements and inputs
Conformant planting records for the site, and for trees delivered with monitoring the acknowledged consignments handed over there (the census frame); a monitoring plan with its period; a monitoring visit record with a declared horizon or none; one tree observation per tree reached with a tree state and at least one geotagged photograph; the NCGS monitoring data requirement.
calculation and transformation rules
Let P be the tree individuals planted at the site (planting records), with, for the delivered-with-monitoring stratum, the trees in the consignment lines the recipient acknowledged there, whose horizons run from the handover date (ADR-0031), O the trees observed on the visit, A the observed trees alive, U = P minus O the unobserved, C_k the observed trees in condition class k, and E the observed trees alive and thriving. Trees alive = |A|. Survival rate = |A| / |O| as a percentage (unobserved excluded from both sides), reported with |U|. Trees by condition class = |C_k| for each k, summing to |O|. Establishment rate, only at T3 or later = |E| / |O| as a percentage. A tree observed as not the one recorded (ncgs:sameTreeAsRecorded false: swapped, or replanted after the first one died) counts as observed and dead, in O and in the dead class, never in A or E, whatever the replacement’s state: the recorded tree is gone. Roll-up over sites, species, strata or places sums the numerators and denominators. O, A, C_k and E count scheduled observations only: of a planted-with-monitoring or delivered-with-monitoring tree, at a declared horizon the monitoring period reaches, at an offset inside its window. Unscheduled observations recorded = the other conformant observations, by stratum, declared horizon or none, alive or dead, site and census place (ADR-0020). Households with a living tree = count of household-stand sites at which at least one tree the programme handed over or planted is observed alive on a visit declaring T2 or later, by horizon and census place; a stand counts once per horizon however many of its trees live. It is a count of stands, not a rate, so a handed-over tree’s observation counts here although it enters no survival rate. For trees delivered with monitoring (ADR-0031), let K be the trees the recipient acknowledged at handover in the stand’s consignment lines: planting uptake at T0+ = trees observed in the ground (ncgs:inGround true) on a scheduled T0+ observation, divided by |K|; survival of delivered trees at a horizon from T1 = trees observed alive at that horizon divided by |K|; in both a tree not observed counts against the rate. T0+ is a planting check, never a survival horizon.
outputs and units of measure
Trees alive at horizon (count, NUM); survival rate at horizon (PERCENT) with unobserved count (NUM); trees by condition class (count, NUM, one value per class); establishment rate at T3 or later (PERCENT); monitoring visits conducted (count, NUM); trees dead by cause of death (count, NUM); living trees with mulch cover (count, NUM); stem diameter of living trees at T3 or later (CentiM); each disaggregated by horizon, species, stratum, site and census place; households with a living tree (count, NUM) at T2 or later, by horizon, census place and the household-stand site type.
validation and verification approach
Verification: a reviewer meeting the KSR requirement in tree establishment and stewardship and in field survey and data capture, who is not the observer, checks that every tree in the planting records is either observed once or listed as unobserved, that each observation counted in a rate lies inside its declared horizon’s window and the rest are counted as unscheduled, that each observation carries a photograph whose geotag lies near the tree’s position, that cause of death appears only on dead trees, and that steward or owner self-reports (observer role steward or owner, channel WhatsApp) are weighted as self-reported. The workflow reaches approved claims only after the latest verification review is APPROVED.
limitations and applicability boundaries
A census on one day; a tree missed on the day is unobserved for that horizon and cannot be back-filled. Condition classes are a field judgement; inter-observer consistency depends on training. Canopy and DBH are seldom measurable before T3. Self-reported observations carry the observer role’s lower evidence grade. Rates are defined for the planted-with-monitoring stratum only: a delivered-only tree (ADR-0003) or an unmonitored planted tree is outside the census frame, and an observation of one is kept as unscheduled (ADR-0020).
rationale
A funder’s contract may be defined on early survival of a monitored stratum; a per-tree census with fixed denominator and explicit unobserved count is the only way that figure can be verified tree by tree rather than reported. Folding condition into the same visit designs the visit once and gives establishment its thriving class without a second methodology.
Applicability
- NCGS-M001: a tree observed on a census visit has a planting record at the visited site or, delivered with monitoring, came in a consignment handed over there; a delivered-only tree is outside the census frame and its observation is unscheduled (ADR-0003, ADR-0020, ADR-0031).
- NCGS-M001: a visit that names an applied methodology must name a monitoring-visit methodology (NCGS-M001, NCGS-M002, NCGS-M004, NCGS-M010, or the provisional NCGS-M005) with activity type monitoring visit.
- NCGS-M001: the census applies under a census sampling design; a visit under a plan that samples its strata is verified under NCGS-M002 (ADR-0016).
- NCGS-M001: every tree observation on the visit carries at least one photograph.
Indicators it serves
- Establishment rate at T3 or later (percent)
- Households with a living tree (count)
- Living trees with mulch cover (count)
- Monitoring visits conducted (count)
- Planting uptake at T0+ (percent)
- Stem diameter of living trees at horizon (centimetres)
- Survival of delivered trees against handover (percent)
- Survival rate at horizon (percent)
- Tree individuals alive at horizon (count)
- Tree individuals by condition class at horizon (count)
- Trees dead by cause of death (count)
- Unscheduled observations recorded (count)
Activity types
- Monitoring visit
Knowledge domains a reviewer needs
- Field survey and data capture
- Tree establishment and stewardship
Variables
| Variable | Role | Unit | Description |
|---|---|---|---|
| Establishment rate (E) | DerivedOutput | PERCENT | E = 100 × |{i in O : a_i and k_i = thriving}| / |O|, defined only when H is T3 or later. |
| Households with a living tree (|H_a|) | DerivedOutput | NUM | |H_a| = count of household-stand sites with at least one tree handed over or planted observed alive (a_i true) on a visit declaring T2 or later; from the visit’s own observations, no survey is needed. |
| Living trees with mulch cover (|M|) | DerivedOutput | NUM | |M| = count of observed trees with a_i true and m_i in {well covered, slightly covered}. |
| Monitoring visits conducted (|V|) | DerivedOutput | NUM | |V| = count of monitoring visit records at the site with at least one observation, by declared horizon or none. |
| Planting uptake at T0+ | DerivedOutput | PERCENT | Trees with g_i true on a scheduled T0+ observation, divided by |K|, as a percentage. |
| Stem diameter of living trees at horizon (dbh) | DerivedOutput | CentiM | dbh_i reported per living tree at T3 or later, summarised as the mean per site, species and place. |
| Survival of delivered trees against handover | DerivedOutput | PERCENT | Trees observed alive on scheduled observations at a horizon from T1, divided by |K|, as a percentage. |
| Survival rate (S) | DerivedOutput | PERCENT | S = 100 × |A| / |O|, unobserved excluded from both sides and |U| reported alongside; rolled up by summing |A| and |O|, never by averaging S. |
| Trees alive at horizon (|A|) | DerivedOutput | NUM | |A| = count of observed trees with a_i true. A tree observed as not the one recorded (ncgs:sameTreeAsRecorded false) is not counted, whatever the replacement’s state: the recorded tree is gone. |
| Trees by condition class (|C_k|) | DerivedOutput | NUM | |C_k| = count of observed trees with k_i = k, for each class k; the classes sum to |O|. |
| Trees dead by cause (|D_c|) | DerivedOutput | NUM | |D_c| = count of observed trees with a_i false and cd_i = c, per cause c. |
| Unobserved (|U|) | DerivedOutput | NUM | |U| = |P| minus |O|: planted trees with no observation on the visit. Reported alongside every rate, never counted as dead. |
| Unscheduled observations recorded (|X|) | DerivedOutput | NUM | |X| = count of conformant tree observations at the site that are not scheduled: not of a planted-with-monitoring tree, or at no declared horizon, a horizon the monitoring period does not reach, or an offset outside its window (ADR-0020). |
| Alive (a_i) | MeasuredInput | UNITLESS | Whether tree i was observed alive on the visit. |
| Cause of death (cd_i) | MeasuredInput | UNITLESS | |
| Condition class (k_i) | MeasuredInput | UNITLESS | The condition class of tree i from the tree-conditions scheme. |
| Declared horizon (H) | MeasuredInput | UNITLESS | |
| In the ground (g_i) | MeasuredInput | UNITLESS | Whether handed-over tree i was in the ground at the T0+ planting check (ADR-0031). |
| Mulch cover (m_i) | MeasuredInput | UNITLESS | |
| Observed tree (o_i) | MeasuredInput | NUM | The tree individual an observation is about; the observed set O. P minus O is the unobserved set U. |
| Offset from planting (d_i) | MeasuredInput | DAY | Days from tree i’s planting date to the observation; outside H’s window the observation is unscheduled and enters no rate (ADR-0020). |
| Planted count (P) | MeasuredInput | NUM | The tree individuals in the site’s planting records: the census frame and the fixed denominator base. |
| Species or cultivar (sp_i) | MeasuredInput | UNITLESS | |
| Stem diameter at breast height (dbh_i) | MeasuredInput | CentiM | |
| Stratum (s_i) | MeasuredInput | UNITLESS | |
| Trees acknowledged at handover (|K|) | MeasuredInput | NUM | The living trees the recipient confirmed in the stand’s consignment lines: the frame for trees delivered with monitoring (ADR-0031). |
Monitoring requirements
- Census at every planned horizon: Every tree individual in the planted-with-monitoring stratum is observed once at each horizon the monitoring plan reaches; a tree not reached is recorded as unobserved for that horizon and the unobserved count is reported with every rate.